Disclosed herein is a painting booth with a coating agent line for conveying a coating agent, in particular in a painting installation, with electrostatic coating agent charging. Further disclosed is a corresponding manufacturing method for a coating agent line of this type.
Modern painting installations to paint motor vehicle body components usually include electrostatic coating agent charging which electrostatically charges paint to be applied so that the paint better adheres to a motor vehicle body component to be painted, which is therefore electrically grounded.
One possibility for electrostatic coating agent charging of this type is so-called direct charging, wherein the paint to be applied itself is electrostatically charged and therefore is at a high electric potential even in the coating agent lines within an applicator (e.g. an atomiser, etc.).
The actual painting in the direct charging example is usually performed by a painting robot within a painting booth, whereby the painting robot is supplied with the paint to be applied through coating agent lines. These coating agent lines run from a paint supply located outside the painting booth to an atomiser on the painting robot, whereby the painting robot additionally carries a high voltage cascade in order to electrostatically charge the paint to be applied. The high voltage necessary for the electrostatic coating agent charging inside the painting booth is a source of danger so that a fire protection device (e.g. sprinkler system, CO2 extinguishing system, fire protection sensor) is installed inside the painting booth which can react in the case of fire to prevent the high voltage of the electrostatic coating agent charging from causing a fire or other damage.
In addition, these conventional painting installations usually have an grounding interface which is arranged inside the painting booth or at least at the booth wall and electrically grounds the coating agent lines here. This prevents any high voltage potential along the coating agent line inside the painting booth from escaping to the outside, which could lead to a fire or other incident. This is made even more important because the fire protection device is arranged inside the painting booth and can only react to high voltage related incidents which occur inside the painting booth. The above-mentioned conventional grounding interfaces for coating agent lines usually have so-called grounding bulkhead plates which are associated with different disadvantages.
Firstly, grounding interfaces of this type require a high number of hose screw connections via which the electrostatically charged coating agent has a connection to the respective grounding connection, whereby up to 56 hose screw connections may be necessary for every painting robot.
Secondly, additional components are required for the mechanical fixing of the conventional grounding interfaces, such as mounting plates, bulkhead plates, bulkhead screwed connections, strain relief, covers, sheeting, etc.
Further, with respect to the painting robots inside a painting booth, different installation possibilities may exist (e.g. top, bottom, directly at the booth wall or at a distance to the booth wall) in accordance with the respective area of use so that the grounding interfaces must also be adjusted accordingly, which makes a standardisation of the grounding interfaces difficult or even impossible. In practice, additional adjustment structures may frequently be necessary in-situ when assembling a painting installation, which makes assembly difficult.
Furthermore, with respect to the state of the art, patent application EP 1 500 435 A2 discloses a piggable coating agent hose, whereby the inner surfaces of the coating agent hose can be electrically conductive. Here, however, the coating agent hose is electrically conductive over its entire length, which is not desired in the inventive coating agent line because the electrical grounding of the coating agent hose is to act only on the grounding side and not on the high voltage side. This conventional, electrically conductive coating agent hose is therefore not suitable in the presently disclosed context.
A painting booth is known from DE 35 26 013 C1 in which the high voltage generator is arranged outside the painting booth.
Finally, reference is to be made to DE 24 55 161 OS, DE 1 965 509 OS, DE 1 246 478 AS and DE 973 208 PS with respect to the state of art.